Field of the Invention
The invention relates to a polymer mixture suitable for use as a sensor mixture.
A polymer mixture of this kind is to be used to determine the mechanical and/or electrical stability or aging of a cable. The corresponding sensor mixture may extend along the cable and form a component of the cross section of an extruded layer of the cable.
Description of Related Art
US 2012/0001128 A1 discloses a semiconductor mixture intended for high-voltage cables, which, with 100 parts by weight of a base polyolefin, contains 0.5 to 2.15 parts by weight of carbon nanotubes and 0.1 to 1 part by weight of a peroxidic crosslinker. The corresponding material is intended for use as an inner conductive layer which surrounds the conductor of a high-voltage cable and as an outer conductive layer which surrounds the insulation thereof.
EP 1 490 672 B1 describes a method for determining the stability of a polymer mixture in a cable by measuring the resistance or the conductivity of another polymer mixture containing 25% by weight of carbon black or metal particles as conductive constituents. Changes in resistance over time are used as a measure of aging, since the aging leads to compaction of the conductive constituents through shrinkage. The polymer mixture comprising conductive constituents may be arranged in the manner of a filament along the cable, in which case the resistance is measured along the polymer mixture.